Sunday, April 19, 2009

Plastic potential

I’ve recently finished reading a book that has made me think about my brain in an entirely new way.

The Brain that Changes Itself by Norman Doidge is an expose of the cutting edge of a new area of science – neuroplasticity.

Doidge is a research psychiatrist and psychoanalyst who is fascinated by the idea of neuroplasticity, a paradigm that is revolutionising neuroscience, the study of the brain and nervous system.

This new paradigm has huge implications for mental illness, brain injuries, the ageing brain, learning disorders and brain events such as strokes.

The old paradigm for understanding the brain was called localisation, and sadly it prevailed for decades despite evidence proving the contrary.

Basically scientists believed that various mental and physical functions were controlled from particular parts of the brain and that the brain itself was ‘hard wired’ in its abilities. If a part of the brain was damaged, it was curtains for whatever functions that part had previously undertaken.

Scientists also thought that children had ‘plastic’ brains only during the crucial developmental years, and that the ability of an adult brain to change was very limited – apart from the fact that it declined! We were told that when you lost brain cells, that was it – they were never coming back.

Doidge calls this way of thinking ‘neurological nihilism’.

In fact, the brain is an instrument we are only just beginning to understand. If one part is damaged, another part can often take over all or some of its functions. Different parts of the brain do hold ‘maps’ of different functions. But the map areas will be taken over by other functions if they aren’t used. Doidge has a maxim he uses throughout the book to explain how it works: ‘Neurons that fire together, wire together’.

And our brains are truly plastic in that they are constantly being remodelled by everything we do. For example, brain maps for particular activities (playing a musical instrument for instance) become more and more complex as our skills develop.

The examples Doidge gives of the potential of the brain to renew itself are incredible. They promise new treatments for autism, serious balance disorders, learning disorders in children, even vision impairment and chronic pain.

Depression treatment based on plasticity
One of the fascinating areas for plasticity is the study of severe depression. Apparently, in some types of depression the prefrontal cortex isn’t working properly. A therapy called ‘repetitive transcranial magnetic stimulation’ (rTMS) uses an electric current to generate a changing magnetic field that penetrates the neurons. This can make the neurons fire and, when done repeatedly, they keep firing.

There is a 70 per cent success rate in the use of this therapy for patients with treatment-resistant depression, and its side effects are fewer than those of depression medication.

A new OCD treatment
A new treatment for OCD that takes account of plasticity is significantly different from traditional treatments in that it isn’t focused on the content of the obsessive thought, but on the process that produces it.

When we make a mistake, a particular part of our brain lets us know. This leads to the ‘nagging feeling’ that we respond to by correcting the mistake. When the mistake is corrected, ideally the uncomfortable feeling goes away.

But in OCD sufferers, the part of the brain that tells us not to worry any more – the caudate nucleus – is, to use Doidge’s term, ‘sticky’. He likens it to an ‘automatic gearshift’ that doesn’t work properly.

Traditional treatments for OCD, in particular exposure therapy and cognitive behavioural therapy (CBT), require the patient to focus on the content of the repetitive thoughts in a bid to reduce their power.

But this new treatment enables patients to use their imaginations and thoughts to shift the gear manually.

An extra benefit is that the treatment can also be used for people who are worriers and obsessive thinkers rather than OCD sufferers. And it’s surprisingly simple.

Basically there are two steps:

First the patient relabels the OCD attack. Here she focuses on the fact that her gearshift is stuck rather than the content of the compulsion. She keeps reminding herself that the OCD is the problem, not the fact that, for example, she’ll be attacked by germs if she doesn’t wash her hands again. She also reminds herself that her mental gearshift is stuck.

The next step is to carry out a pleasurable activity, for up to 30 minutes, right at the moment the attack starts.

According to Doidge, when patients work on this therapy, they are literally altering their caudate, and strengthening their ‘manual transmission’. Of course, this therapy takes time – the anxiety about not carrying out the compulsion will still be there, at least at first.

Combatting the ageing brain
Scientists working in the area of neuroplasticity have devised ways to tackle the causes of cognitive decline and not just the symptoms.

The nucleus basalis is the part of the brain that sets off the critical learning period in children. It is always on during the critical period – hence the incredible ability of the young to learn.

But adults use their nucleus basalis only when they are really engaged with something and giving it their full attention. That’s what helps us to learn well.

Trouble with memory is due to an atrophying of the nucleus basalis. Anything that requires focused attention improves its functioning.

Learning new skills is a great way of improving the nucleus basilis because it thrives on novelty and being engaged. It’s important to choose an activity that you’re really drawn to so that you will be deeply engaged. A particularly useful thing to do is to learn a new language.

Other traditional practices that improve brain plasticity in a more general sense include learning a musical instrument, meditation, the Feldenkrais method, tai chi and exercise. (Doidge is particularly enthusiastic about tai chi.)

Neuroplastician Michael Merzenich, along with a team of scientists, has devised exercises to improve adult memory based on the principles outlined above. His company, Posit Science, has developed exercises for adults that help people to process sound better – the first step to strengthening memory – because they stimulate the nucleus basalis.

Better rehabilitation for strokes
Neuroplasticians have proved that people who have suffered devastating strokes can regain many functions, even if the parts of the brain involved in movement are irrevocably damaged.

Edward Taub has pioneered Constraint Induced Movement Therapy, based on neuroplasticity. It’s far more intensive than conventional rehabilitation, features constant repetitions of very basic movements that are designed to be incrementally more challenging, and forces patients to use the damaged parts of the body, rather than letting the undamaged parts take over – the principle of ‘use it or lose it’.

Doidge also tells the story of a stroke victim in his late sixties who after conventional rehabilitation was unable to move. His medical student son took him back to the basics, literally teaching him to crawl again, then walk, and so on. A year later he was functioning and seven years later he was mountain climbing.

Implications for positive thinking
There were so many questions that this book raised for me – many more than it answered. As one of the first attempts to popularise this emerging science in book form, it’s as much a signpost to future possibilities as a description of current treatments.

The following text appears on some editions of the front cover of the book: ‘The power of positive thinking finally gains scientific credibility’. This is very misleading: the book isn’t in the main about positive thinking. But if the book’s findings have implications for positive thinking – and they seem to – this raises many questions in itself.

Positive thinking holds dangers for an obsessive like me. I tried it for years and it would get my brain into a bit of a state. I think this is because it’s a basic denial of the current reality.

For example, I might say to myself ‘I now have a wonderful new job that recognises my skills, with fantastic pay and flexible hours.’ But the fact is I don’t. So my brain is confused and strained because I’m asking it to believe something that isn’t true. At least one new age practitioner has also denounced positive thinking.

Although Doidge’s book doesn’t delve into positive thinking, it gives convincing examples of studies showing that imagining you’re practising a skill can have similar benefits for improving that skill as actually practising it. So it seems some versions of visualising at least may be useful.

Implications for mindfulness
Perhaps the thing that bothers me most about this kind of finding is its implications for mindfulness.

This is a practice increasingly used to combat, among other things, anxiety and depression and it’s derived from ancient Buddhist teachings.

The theory is that, at least initially, you don’t actually try to change your thoughts and feelings. You simply observe them in a detached, non-judgemental, attentive way.

Mindfulness seems to focus on developing the observer part of the brain to help the sufferer understand that the thoughts and feelings are not real, but just the natural fluctuations of the mind. In this sense it's supposed to improve attentiveness because it gently forces the brain to focus on the present moment -- surely a similar aim to that of the exercises, discussed above, that improve adult memory?

It’s also very concerned with minimising the kind of self-analysis that tends to make things worse.

I practise mindfulness in a very lazy way and I feel it’s helped me move a little bit more into reality. It hasn’t cured me by any means, and sometimes it falls by the wayside because my brain just becomes too busy to attend to itself.

But Doidge’s theory seems to suggest that we have to work at making our brains stronger, that we need to focus our thoughts and always use them actively in order to change. This in some ways seems to contradict the theory behind mindfulness.

Again, I hope that in a future book he deals with this issue in relation to two questions: Is mindfulness useful and if so, what is it about the plastic brain that makes it so?

Are there other, more effective treatments for anxiety that relate to plasticity?

Perhaps there are ways that the brain’s plasticity can be deployed to give people a more positive outlook without the brain actually having to lie to itself!

General questions
The material on the ageing brain really interested me and made me think about my own brain, which is subject to allergy-induced brain fog, the effects of insomnia and the clouds of anxiety. Could I improve my poor memory just by, say, learning a language?

The last time I tried to learn French I was shown to be a very mediocre student whereas in earlier years I’d been quite quick so I got discouraged. But Doidge says two interesting things.

He states that it takes six months for a new skill to really lodge in the brain (I didn’t give the French six months). But he also suggests that learning a language will improve the brain anyway – the implication is that the learning process rather than any proficiency gained is the important thing, but this isn’t explored very thoroughly. (If this were the case it would greatly improve my motivation.)

And what about my seemingly futile keyboard thumpings, which I gave up because without tuition I wasn’t improving? Were they worthwhile for their own sake, in helping me be a better editor, for instance?

The website publicising the book doesn’t allow for direct questions to Doidge – it appears there were so many queries that he was no longer able to answer them. The book is now available in over 70 countries and has set off a wellspring of interest from people with conditions that could benefit from plasticity-based treatments.

A documentary of the same name has been made. Doidge is still researching neuroplasticity, so let’s hope a sequel is in the offing.

Doidge will be in Australia next month, to speak at the Sydney Writers Festival on 18 May.


  1. Hello SlightlyNutty.

    I was enthralled by Doidge's book, too. At every turn I found myself thinking "why have I never heard of this before." The research and science is so far ahead of what the general public is aware of. Good for Doidge to track it all down and put it all together.

    My company publishes a brain training product that taps into the brain's ability to adapt and change. It trains some of the core brain functions (working memory, focus, multi-tasking) to produce plastic change in the way that Doidge describes. The fascinating thing is that customers report a broad range of benefits from the training, from simple increases in memory and focus to increased musical aptitude.

    Anyway, I liked your post and thought I would connect. I thought you may be interested in the software - Brain Fitness Pro.

    Martin Walker

  2. Hi Martin,

    Thanks for dropping by the blog and commenting. Your website looks interesting and the software is very reasonably priced compared with that of Posit Science.

    My one concern is the website's claim that the software 'employs the only training method scientifically proven to make users smarter'. I would guess that Posit Science might say something similar about their software.

    However, it's good to have a bit of competition in this emerging market!